The object of this work is to study pathophysiological changes in experimental head injury with the purpose of designing interventional therapy. We will continue using our established gun shot model in the monkey and extend the study from six hours to 24 and eventually 48 hours. We will initiate the acceleration model and study vital signs, cerebral blood flow, cerebrovascular resistance, CMRO2, CMR lactate, somatic evoked potentials, and cardiac output. We will also continue an in vitro study of vaso-active drugs (in relation to blood flow) and a biochemical study of a glial maturation protein (in relation to glial scan). BIBLIOGRAPHIC REFERENCES: Crockard, H.A., Brown, F.D., Johns, L.M. and Mullan, S. An experimental cerebral missile injury in primates. J. Neurosurg, 1977 (in press). Crockard, H.A., Brown, F.D., Calica, A.B., Johns, L.M. and Mullan, S. Physiological consequences of experimental cerebral missile injury and the use of data analysis to predict survival. J. Neurosurg, 1977 (in press).